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[Joe Thierry]

How many times can you passively split a line level signal without having issues?

Thanks,
Joe

[Arthur Skudra]

It's determined by the output impedance of the "sending" unit vs. the combined input impedance of the "receiving" units.  Generally I try to keep it to no less than a 10:1 ratio input vs. output impedance respectively.

Some interesting reading here:
http://www.rane.com/note124.html

[John Roberts {JR}]

Joe Thierry wrote on Mon, 03 August 2009 21:45

How many times can you passively split a line level signal without having issues? Thanks, Joe

The answer depends on specifics about the products used, and how you define "issues".

Unless you are doing something unusual this is probably not a concern. Most professional gear is designed with adequately low output drive capability (not to be confused with output impedance) , and adequately high input impedance (which is exactly what it sounds like), to tolerate several splits.

I would be careful about less than professional gear which may not have much output drive capability, or oddball inputs with lower than normal terminations. If trying to split more than a handful of boxes check the data sheets and do the math.

For a good split the worst consequence a fractional dB insertion loss, for worst case, distortion on signal peaks and perhaps HF/LF loss.

JR

[Tim Weaver]

Whirlwind feels very comfortable about splitting a signal up to 6 times.....

[Greg Cameron]

You can likely go a lot more than that with many typical devices. ≥20kΩ balanced inputs are common and ≤100Ω balanced outputs are common as well. Of course like JR said, you have to check the specs for your particular items and calculate accordingly. But with say a 100Ω balanced mixer output and several amps channels with 20kΩ inputs, you could in theory split the mixer output into at least 16 inputs (1.25kΩ) and still maintain a 10:1 input to output impedance relationship.

Greg

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